The Dolphins were dealt a crushing blow last Saturday when Dustin Keller shattered his knee against the Houston Texans. The pass-catching tight end is out for the season, but it's a mistake to write off Miami's passing game, according to Greg Cosell.

"After watching (Dolphins) tape, believe it or not, I don't think (Keller's) as big a loss as we would have thought," Cosell said on Thursday's FantasyGuru.com podcast. "I was really impressed with Tannehill's development. ... Maybe there's not one player who would put up the specific numbers we thought Keller would, but I don't think this short-circuits their pass game because of Tannehill's development. So I still think they'll have a very solid pass game."

One early obstacle is an offensive line with questions at left tackle and right guard.

Miami's front has ranked as the fourth-worst run-blocking unit in the league during the preseason, per Pro Football Focus. The unit has shown better on passing downs (ranking 15th), but Tannehill -- yet to throw a pick in the preseason -- has made plenty of plays from a collapsing pocket. He displayed that ability last season, too, completing 50.8 percent of his throws under pressure, seventh best in the NFL, according to PFF. Strip away dropped passes, and that figure rose to 72.9 percent, second only to Robert Griffin III.

Cosell wasn't in love with Mike Wallace's route-running in his first preseason appearance for the Dolphins, but he thought Tannehill showed great poise connecting with his new receiver on a 9-yard touchdown strike in the first quarter.

"Incredible anticipation in the red zone, where everything has to happen faster," Cosell said. "It was an incredibly tight window. (Tannehill) understood the coverage, got rid of the ball incredibly quickly. Those are throws that don't look difficult if you're just watching them on TV because it appears that the receiver's open and anybody can make that throw -- but that was an incredibly advanced NFL red-zone throw."

That's four "incredibles" on one play. Heady praise for the young QB, and we don't disagree. If Tannehill's development continues upward, losing Keller -- as rough as it might seem on paper -- won't stop the Dolphins from a productive passing game. Big-time quarterback play covers many sins.